NoPhenotype is a clone of StackOverflow built on Rails and Backbone. Users can:
To implement infinite scroll combined with sorting questions by popularity (first by number of votes, then by number of answers), all questions must be first sorted in the backend. This is accomplished with ActiveRecord queries by joining and ordering questions, votes, and answers tables.
def self.sort_by_popularity
subquery = Question.select("questions.*, SUM(COALESCE(votes.value, 0)) AS votes_count")
.joins("LEFT OUTER JOIN votes ON questions.id = votes.votable_id")
.where("votes.votable_type IS NULL OR votes.votable_type = 'Question'")
.group("questions.id")
res = Question.select("a.*, COUNT(answers.id) AS answer_count")
.from(subquery, :a)
.joins("LEFT OUTER JOIN answers ON a.id = answers.question_id")
.group("a.id, a.title, a.content, a.created_at, a.updated_at, a.user_id, a.votes_count")
.order("a.votes_count DESC, COUNT(answers.id) DESC, a.created_at DESC")
res
end
def index
...
elsif params[:sort].present?
@questions = Kaminari::paginate_array(
Question.sort_by_popularity.to_a
).page(params[:page]).per(7)
render :index
...
end
Implement questions in both the back-end and front-end. With Backbone front end, have questions index view, questions index item view (used for subviews), show view for individual questions, and form for creating new questions. In the back-end, add API routes to post data as JSON, then user jBuilder as a means for the Backbone models to fetch data from those routes.
Implement user authentication. Users can sign up/sign in (username, email, password) and sign out. Users are redirected to root (questions index page) upon logging in.
Build associations between the User model and Question model.
Add more API routes (for answers). Build associations between Question/Answer/User models (in both the front-end and back-end). The ultimate goal will be to display answers on question's show page with user's username.
Continue to work on questions index page to display number of answers the question has.
Users can create tags for questions. Build association between Tag and Question models (through Taggings). Make a tags index page with links (by the tag name) to the tag show page. Show page will have questions tagged with that particular tag. Clicking on question (title) will bring to the question show page.
Continue working on question index and show pages so that tags for that question are displayed.
Build Comment(s) MVC in both the front-end and back-end. (C = controller in the back-end and collection in the front-end). Use polymorphic association. By the end of this phase, users will be able to comment on answers and questions. The idea is for comments to be displayed on answer show view (which is itself a subview of question show page) and question show view.
Users can upvote and downvote both questions and answers. Questions and Answer show view display NET number of upvotes and downvotes. (Upvote - downvote). Users can only vote on a specific question and answer once. Restriction is implemented such that a second vote on the model deletes the previous one from the database.
User who asked a question can accept an answer for the question. Accepting an answer makes a green checkmark visible on the answer show view.
Basic profile page (picture, username, short bio)